On Tue, Jan 10, 2012 at 07:12:50AM -0800, Ian Lance Taylor wrote: > Basile Starynkevitch <bas...@starynkevitch.net> writes: > > > I am fighting against makefile issues on the GCC MELT branch. > > > > Much more details are given in > > http://stackoverflow.com/q/8727896/841108 > > and in > > http://lists.gnu.org/archive/html/help-make/2012-01/msg00017.html > > > > So (unless you ask) I won't repeat them here. > > > > (and the bugs affect mostly me, not the usual MELT user) > > > > The symptoms are: > > > > 1. make -j don't work > > > > 2. "make ; make" is running a lot of useless commands for the > > second make and it should not > > > > > > I probably am not understanding when stampfiles in Makefiles should be > > used. The main point is that MELT cares much more about file contents > > than file timestamps. > > Your stackoverflow question has way too much detail for me to > understand. I think you need to debug this like any other issue: reduce > to the minimal test case. > > Stamp files in make work like this: > > FILE: STAMP-FILE; @true > STAMP-FILE: DEPENDENCIES > commands to create FILE.tmp > move-if-change FILE.tmp FILE > touch $@ > > What this says is: if any of DEPENDENCIES change, then run the commands > to create FILE.tmp. The move-if-change shell script then compares > FILE.tmp and FILE; if they are different, it moves FILE.tmp to FILE, > updating the timestamp. If they are not different, FILE is left > unchanged, with the same timestamp.
A big thanks for the reply. Then I can ask the next question: when should I use time stamps files? Only for dependencies upon content, or something else? Cheers. -- Basile STARYNKEVITCH http://starynkevitch.net/Basile/ email: basile<at>starynkevitch<dot>net mobile: +33 6 8501 2359 8, rue de la Faiencerie, 92340 Bourg La Reine, France *** opinions {are only mines, sont seulement les miennes} ***
